st150 mk6 a/c not working

[jokke]

hi there,
my a/c has never worked since i bought it last summer.
at first, while pressing the button it lit up but when releasing the light went out.
i had it re-gassed and since then if i press the button it keeps lit. but the compressor will not turn on/ relay does not click.
i changed both pressure sensors under the headlight and on the line next to it but no result.
when i squeeze the relay next to the battery manually, the compressor does come on. i have already replaced this relay so it must not get activated.
i have replaced the heater controls but no luck. measured continuity in the wires from heater controls to the pcm and they are all good.
the cooling fan also does not come on when pressing the button so i think something is preventing the pcm from turning it on or it is not getting a signal.
re-gassing did make a change in the button keeping lit so i believe the pcm is communicating with the heater controls.

i am running out of ideas here, does anybody know something else i can try?
can the pcm just go bad?

hope to get this thing sorted finally..
thanks in advance,
johan

 

[TyphoonFiST]

The only thing I could think of is a software update or PCM Re-flash. Sometimes when you replace HVAC head units they need to also need to re-learn their job after install.

 

[jokke]

ok thanks, will stop by the dealer for an update then